a 2 uF capacitor is connected in series with a 1.2 M ohms resistor and a 5 v battery for a long time. What is the current in the resistor 1s after disconnecting the battery?

Current starts out at V/R, at t = 0, but decays so that

I(t) = (V/R)*e^(-t/RC)

In this case, RC = 2.4 seconds
V/R = 4.17*10^-6 amps

I(t=1s) = 4.17*10^-6*e^-0.4167
= 2.75 microamps